module vga_display(
	input 		[7:0] 	display_y,
    input             vga_clk,                  
    input             sys_rst_n,                
    
    input      [ 9:0] pixel_xpos,               
    input      [ 9:0] pixel_ypos,                   
    output reg [15:0] pixel_data                
    );    
    
parameter  H_DISP = 10'd640;                    
parameter  V_DISP = 10'd480;                    
localparam WHITE  = 16'b11111_111111_11111;     
localparam BLACK  = 16'b00000_000000_00000;     
localparam RED    = 16'b11111_000000_00000;     
localparam GREEN  = 16'b00000_111111_00000;     
localparam BLUE   = 16'b00000_000000_11111;     
    

always @(posedge vga_clk or negedge sys_rst_n) begin         
    if (!sys_rst_n)
        pixel_data <= 16'd0;                                  
    else begin
		if(pixel_ypos >= {display_y,2'b00} && pixel_ypos <= {display_y,2'b11}) pixel_data = WHITE;
		else pixel_data = BLACK;
    end
end

endmodule 